Validation of Shock Index Pediatric-Adjusted (SIPA) for Children Injured in Warzones

Christopher W Marenco, Woo S Do, Daniel T Lammers, John D Horton, Kenneth Azarow, Matthew J Eckert

J Trauma Acute Care Surg 2020 Mar 12; Online ahead of print.

Background: Shock Index Pediatric-Adjusted (SIPA) has been used to predict injury severity and outcomes after civilian pediatric trauma. We hypothesize that SIPA can predict the need for blood transfusion and emergent surgery among pediatric patients injured in warzones, where resources are limited and accurate triage is essential.

Methods: Retrospective review of the DoD Trauma Registry for all patients ≤17years, from 2008-2015. SIPA was determined using vital signs recorded upon arrival to the initial level of care. Patients were classified into two groups (normal v. elevated SIPA) using age-specific threshold values. Need for blood product transfusion (BPT) within 24 hours and emergent surgical procedures (ESP) was compared between groups. ICU admission, injury severity, and mortality were also compared. Regression analysis was performed to evaluate the relationship between SIPA and primary outcomes.

Results: 2121 patients were included with mean ISS 12±10. The mechanism of injury was penetrating (63%), blunt (25%), and burns (12%). Patients with an elevated SIPA (43%) had significantly greater need for BPT (49.2% v. 25.0%) and ESP (22.9% v. 16.0%), as well as mortality (10.3% v. 4.8%) and ICU admission (49.9% v. 36.1%), all p<0.001. Regression analysis confirmed an elevated SIPA as independently associated with both BPT (OR=2.36, 95% CI 1.19-2.94, p<0.001) and ESP (OR=1.29, 95% CI 1.01-1.64, p=0.044).

Conclusion: This is the first study of SIPA in pediatric warzone trauma. Elevated SIPA is associated with significantly increased need for blood product transfusion and emergent surgery, and may therefore serve as a valuable tool for planning and triage in austere settings.